Improvement in lawn-mowers



G. EQBURT. Lawn-Mower.

No. 220,120. Patented Sept. 30,1879.

N.PETEHS. PHOTO-LITHOGRAPHER, WASHINGTON, D C.

UNITED STATES PATENT OFFICE.

GEORGE E. BURT, OF HARVARD, MASSACHUSETTS.

IMPROVEM ENT -l N LAWN-MQVVERS.

Specification forming part of Letters Patent No. 220,120, dated September 30, 1879; application liled April 12, 1879.

To all whom t may concer-a:

Bc it known that I, GEORGE EDWARD BURT, ot' Harvard, in the county of Worcester, State of Massachusetts, have invented a new and useful Improvementl in Lawn-Mowers, of which the following is a specification.

The invention relates to the arrangement and combination of supporting and propelling mechanism and protecting-guards, and a device for supporting and adjusting the revolving cutter of lawn-mowers.

Heretoforelawn-mowers have been supported by wheels having axles to hold them in position, and the cutting mechanism has been propelledby cogs or chain, and such gearing has been protected by disks or plates covering the entire area ot' the supporting-wheels. When the gearing is within the wheels, it'iudependent gearing is used, it requires extra boxing and supporting-wheels. These methods of construction are expensive, and a large amount of power is consumed in transmitting the force applied by the operator in propelling the mower. y

In the accompanying drawings, in which similar letters of reference indicate like parts, Figure l is a perspective, view of a lawnmower withmy device. Fig. 2 is a horizontal longitudinal section of the same through the center of one of the transmitting-rolls and the head of the revolving cutter, the stationary step, chill-hardened step-seat, oil-chamber, &c. Fig. 3 is a detail view ofthe eccentric step, revolving-cutter head, and the device by which the step is held rmly in position. Fig. 4. is a view of the eccentric step H.

The main frame B is cast in one piece and mounted on two supporting and propelling rings, A A, which are held in position by the transmitting-rolls C O C" and guardcase E.

On the main frame B, Icast projectin gilan ges D. These strengthen the frame and serve as guards to cover and protect the lower internal section of the ring A. The guard-case E is constructed with flanges to cover thetransmitting-rolls C O' G also with the arpstyto cover and protect the upper internal section of the ring A.

F is a hollow boss on the case E, which makes the seat for the step B. I is a set y screwholding the step in place.

Cases E and frame B are constructed with seats or boxes for the pivots of the transmit ting-rolls to revolve in. K is the gagewheel, held by screw Y in the projecting' arm Z on the main frame Band case E. ScrewLpasses through the rearward projection W on the case E, securely and firmly attaching the case and rolls C C C to the main frame B. (Shown in Fig. l.) y.

The supportin g-rin gs A are constructed with recesses in their periphery for a seat to rubber bands O. (Shown in Fig. 2.) P is revolving cutter, which I make with independent heads, having chill-hardened tapering seats, which revolve inside of the main frame B on steps H, which are made eccentric, having an oil-chamber, with a small outlet in the point of the `taper eccentric to lubricate the bearing of the revolving cutter; also a small outlet near the center of the bearing ofthe transmitting rolls C. The outer end of the chamber is closed by the screw J. These steps are rmly held in any posit-ion in the hollow boss F by` the set-screw I, as shown in Fig. 3. P P are revolving cutters, constructed of angle-iron.

I make the revolving heads Q with seats B, which form a firm bed for the cutters to rest in, and are securely ixed to the revolving heads. B is the cutter-bar, cast on and making part of the main frame B. T is the cutting-blade, made of steel or any good cutting material, and fastened to the cutter-bar B. M is the handle, secured to the main frame by the projecting standard S, fastened to center of `the cutter-bar and cross-bar of the main frame. rI he standard is made with aslot, so that by means of a thumb-nut the handle can be firmly held at any angle desirable. The propelling-roll C revolves on the step H. The revolving heads Q Q are constructed to form ratchets by means of teeth cast on the heads, and spring-starts made to work in slots parallel with the peri phery of the transmitting-rolls, and are actuated by spiral springs inthe rear of the starts.

Operation: When the operator pushes the mower he presses down on the handle M on the main frame, which rests on the pivots ot' the transmitting-mills C C. Their periphery rests on the arcs of the ring A, which rests on the ground. It will be seen that the weight of the main frame, rolls, and cutter all rest on the transmitting-rolls C C', and they rest on the arcs of the ring A. This causes the transmttingrolls C to press against roll L" and each other with force sufficient to propel the revolving cutter; and as this force acts on both sides ot' the propelling-roll (j, the ctl'ective force of the operator on the cutter is more than when transmitted through either internal or external cogs, as have been heretofore employed.

It will be seen b v constructing the frame of one casting it can be made lighter and save the expense of putting the parts together; and by the use of rubber bands the traction on the grass when in operation is much greater. The `gage-Wheel gages the cutter-bar to the right height. By loosening the set-screw I and turning the step H, which is made eccentric, the cutter-blades of the revolving` reel can be very quickly and nicely adjusted with reference to the stationary cutter-blade T. This is a cheap and effective method to compensate for the wear and grinding awayof' the cuttingedges of the revolving cutter and blade.

When the boxes and journals to the revolving cutter of the mower become worn they do not operate, as it lets the cutting-edges apart. To overcome this dillicultY l use the device of a tapering step, constructed to move endwise. Thus the Wear ot' the bearings or pivots of the revolving,r cutter can be easily taken up by loosening the set-screw I and moving the step H endwise. Then, turning,r down the screw 1,2111 the parts are firmly held in position, and the looseness caused by the weer is taken up, leaving the cutter perfectl)Y free to revolve. This is a very simple operation, and the operative parts are cheaper to make than the common boxes, bearings, and bolts.

The chill hardened seats and ecccntrics or steps are very durable. The standard S being attached to the cutter-berend main frame makes them verf;v lrm. The seats in the heads of re volving cutter form shouldersfor the angle-iron cutters to rest against, and hold both heads ot' the reel so it cannot twist by the force of the propelling-rings, for by means ot' the ratchet either ot the rings can propel the revolving cutter. The internal face of thc ring A is completely covered by the arc G and flange l) and case Fl. The transmitting-rolls C U' C are also covered by the case E and the main frame, so that nothing like grass, stubble, or stones can choke or injure them, still leaving the face of the ring open and light.

What l claim is- 1. In a lawn-mower, the combination, with the revolving cutters, of the supporting-rings A A and intermediate transmitting-rollers, adapted to communicate motion to the cutter from the rings, substantially as described.

2. As a means for adjusting the revolving cutter of a lawn-mower, the combination of the cutter, having bearings at its ends, with the eccentric snpportingstep and means for turning and holding said step, substantially as described, for the purpose set forth.

3. In a lawn-mower, the combination of the guard-case E, the arc G, the flange D, and thc main frame B, constructed and arranged to protect the internal surface of the ring A and cover the transmitting-rolls, Substantially as described.

GEORGE EDWARD BURT.

Witnesses LEVI SHERWIN, WILLIAM M. SHERWIN. 

